The present invention relates to a method of producing a membrane module for fluid purifiers, wherein sheets of membrane material are disposed in layers with spacing elements placed therebetween, such as to obtain respective mutually alternating spaces or cavities in which contaminated and purified fluid are accommodated. The invention also relates to a membrane module produced in accordance with the method.
According to one known method, the module is constructed of flat membrane sheets stretched between rigid support frames. Although this known method can be mechanized to a large extent, the resultant modules have low volume efficiency (active membrane surface area/module volume), primarily due to the thickness and sealing efficiency of the rigid frames.
According to another known method, the membrane module is produced by helically winding a plurality of membrane envelopes around a permeation tube. Although this method produces modules which have a high volume efficiency, it can only be mechanized to a small extent, since the task of helically winding and gluing the membrane envelopes must be carried out with extreme care in order to avoid folds and wrinkles on the inner surfaces of the envelopes, such folds and wrinkles causing the membrane material to rupture and therewith render it useless.
Another problem encountered with these and other known membrane modules is the difficulty of readily placing the large number of spaces intended for accommodating purified fluid in fluid-tight communication with a fluid purifier outlet line that is common to all these spaces.